Description: The importation of e-waste from developed countries to developing countries like Ghana and other countries in West Africa is currently occurring on a massive scale, and is only expected to increase over time. Despite the potential risks presented by occupational and community exposures to e-waste, few studies have examined the health effects of this waste on human health in this region. Heavy metals exposures have been documented at e-waste sites in Asia, but exposures to heavy metals near e-waste sites in Ghana have not been assessed. Additionally, a handful of studies have found an association between heavy metals exposures and hearing loss (HL) in humans, but no studies have examined this possible association among workers and community members near e-waste sites. Furthermore, no studies appear to have evaluated the possible influence of nutritional status on the relationship between heavy metals and hearing loss, despite the fact that metallic essential nutrients may be protective against HL since they compete with non-essential heavy metals during uptake.

We proposed to evaluate heavy metals exposures and hearing levels at Agbogbloshie, one of the largest e-waste sites in Africa, with three specific aims:

Specific Aim 1: To investigate the extent to which various levels of heavy metal exposures (Pb and Cd) are associated with hearing damage. We will assess heavy metals exposures through assessment of blood and urine biomarkers among 60 participating subjects.

Specific Aim 2: To investigate the extent to which detrimental effects on hearing due to heavy metal exposures (Pb and Cd) are modified by nutritional factors (blood levels of calcium, iron, copper, and zinc) and noise exposures. We will assess nutritional status using self-reported dietary intake and blood biomarkers for each subject. Hearing levels will be assessed using audiometric testing, and noise exposures will be measured for 24 consecutive hours on all subjects using personal noise dosimeters.

Specific Aim 3: To investigate the relationship between noise exposures and physiological stress. We will assess physiological stress through two quantitative measures, salivary cortisol and heart rate, and will compare these measures to noise exposures.